Xu Yaohui, Li Ruixing, Zhou Yang
School of Physics and Electronic Engineering, Laboratory for Functional Materials, Leshan Normal University Leshan Sichuan 614004 China.
Key Laboratory of Aerospace Materials and Performance (Ministry of Education), School of Materials Science and Engineering, Beihang University Beijing 100191 China.
RSC Adv. 2019 Jul 18;9(39):22366-22375. doi: 10.1039/c9ra02294e. eCollection 2019 Jul 17.
An eco-friendly route was developed for the synthesis of mesoporous CeO powders without any additional template. The original cerium precursors were separated from Ce aqueous solution by (NH)CO or NaCO a chemical precipitation method, then HO was introduced to induce the phase transformation from original cerium precursors to CeO precursors with initial porous structures, finally the crystallinities of CeO precursors were improved by a hydrothermal treatment, meanwhile the mesoporous structures of final CeO powders were formed. The BET surface areas of mesoporous CeO powders synthesized using (NH)CO and NaCO as precipitants were 106.1 and 76.9 m g, respectively. Moreover, a mesoporous CeO sample with BET surface area of 100.0 m g was also synthesized using commercial Ce(CO)·HO as an existing cerium precursor under the same conditions as control, which could shorten experimental processes and reduce costs. The oxidation-induced phase transformation from original cerium precursors to CeO precursors with initial porous structures was the precondition for further forming of mesoporous structures of final CeO powders during the hydrothermal process. These mesoporous CeO powders showed the rapid and effective adsorption for acid orange 7 dye from simulated wastewater without pH pre-adjustment at room temperature. Furthermore, the adsorption capacities of these mesoporous CeO powders for removal of acid orange 7 dye were determined according to the Langmuir linear fits.
开发了一种无额外模板合成介孔CeO粉末的环保路线。通过(NH₄)₂CO₃或Na₂CO₃化学沉淀法将原始铈前驱体从铈水溶液中分离出来，然后引入H₂O₂诱导原始铈前驱体向具有初始多孔结构的CeO₂前驱体进行相变，最后通过水热处理提高CeO₂前驱体的结晶度，同时形成最终介孔CeO粉末的介孔结构。以(NH₄)₂CO₃和Na₂CO₃作为沉淀剂合成的介孔CeO粉末的BET表面积分别为106.1和76.9 m²/g。此外，在相同条件下，使用市售Ce(CO₃)₃·3H₂O作为现有铈前驱体合成了BET表面积为100.0 m²/g的介孔CeO样品作为对照，这可以缩短实验过程并降低成本。从原始铈前驱体到具有初始多孔结构的CeO₂前驱体的氧化诱导相变是水热过程中最终CeO粉末进一步形成介孔结构的前提条件。这些介孔CeO粉末在室温下无需预先调节pH值即可对模拟废水中的酸性橙7染料表现出快速有效的吸附。此外，根据Langmuir线性拟合确定了这些介孔CeO粉末对酸性橙7染料的吸附容量。
